Plantation owner Stanley Preston is found decapitated at Bloody Bridge, with a coffin strap marked for King Charles I lying near the body. Preston's family ties to the Home Secretary and his wealth from West Indian slavery ensure that both the government and Sebastian's father-in-law take an interest in the case.
Sebastian and Hero question collectors, servants and members of Preston's family, including people connected with Jane Austen's circle. A second murder and the return of Sebastian's former commander Lord Oliphant reveal that the historical relic is only one part of a threat rooted in wartime betrayal and colonial exploitation.